2002 TB running problems

[jhubbhard]

As an ex-mechanic (20 years ago) this vehicle has me stumped and I would appreciate any help. Wife drove car home fine, gets up next morning and car is running like crap. Used scan toll and got a P0300. Against my better training I started changing parts. First the plugs with new AC Iridium units, then all new coil packs, fuel filter (the old one had mud in it) and cam position sensor. Figured the fuel injectors might be full of crap. Pulled it all down and disassembled the fuel rail and injectors. Cleaned the rail and soaked the injectors and blew out with air pressure (there was crap in them). Reassembled all with new intake gaskets and changed valve cover gasket at the same time (noticed a little oil pooling in the plug wells). Now the fun part, tried to start and will crank but not run. Fuel pump does run, car smells like it might be flooding. It acts like it is trying to fire but just not quite there. Ran scan tool again but no codes. I NEED HELP PLEASE.

Forgot to mention that I removed and cleaned the throttle body.

 

[The_Roadie]

Welcome!

Boy you did a lot of stuff all at once. I'd be most suspicious of a bent pin on one of the connectors you took off. Or missing a sensor or injector connection. If you take off the air intake hose, can you see the throttle body butterfly valve move and initialize itself when you turn the ignition on?

 

[gmcman]

Someone just went through a similar situation and he accidently swapped the ignition or injector harness with the throttle body harness, apparently they have the same connector.

How long did the vehicle sit before the wife drove it, that's a lot of maintenance but hey, at least all the parts are new. This motor is sensitive to specific AC Delco parts only, sometimes aftermarket works, sometimes only for a short while.

 

[Wooluf1952]

Welcome


In case you haven't heard:
http://gmtnation.com/forums/topic/218-welcome-to-gmtnationcom-heres-the-story/



The original rough running could also be tied to the Fuel Pressure Regulator.

 

[jhubbhard]

I accidently had swapped the connectors but realized this prior to starting. The vehicle had only sat overnight. I have tried inspecting every fuse in the engine fuse box as well. I have recently learned that the TB do not like to have the batt ery disconnected even though alldata instructs you to do so. How can I get the pcm to relearn if the vehicle won't run? I removed vacuum hose from FPR and it didn't smell of gas.

 

[kickass audio]

You don't have to do a PCM relearn as long as your security light does not flash on the cluster when you try to turn the truck on or have key in Run without starting it. PCM's that are swapped from one vehicle to another need to be relearned as it treats it as if it is stolen. I played with my PCM before by getting the truck to run and turning the key to off and back to run really fast and it revs up the engine then it sometimes dies and flashes the security light. (i know its bad to do that but i just wanted to try it for shits and giggles)

Anyway have you tried to check your fuel pressure to ensure you are getting enough pressure? Have you tested each plug to make sure they are all getting spark? Those are just a few things I do when I can't get it to catch when i start.

 

[gmcman]

Is the crank sensor connected?

 

[jhubbhard]

tested fuel pressure and it was fine. decided to reinstall old coil packs - cranked right up. still a little rough running. hoping it is just the pcm recalibrating. pulled code as P0303 so I swapped #3 & 3 coil packs. cleared code and retest drove. now getting a P0302 so I gtues I am off to bu a new Delphi coil pack. TB owners be wary of purchasing 6 packs of coil packs online for unbelievable prices. they work for awhile and then start to fail. lesson learned. thanks for all the input.

 

[gmcman]

That's great and I'm curious if the new coil packs have the springs installed